Double-control device for phonographs



15x9, 1930. I W BIK FF' 1,784,159

DOUBLE CONTROL DEVICE FOR PHONOGRAPHS Filed lay 10, 1929 F )1" w n..\ m

Patented Dec. 9, 1930 r UNITED STATES PATENT OFFICE WASSILY REBIKOFF, OF PARIS, FRANCE, ASSIGNOR TO LEON IDE DAVYDOFF, F PARIS, FRANCE DOUBLE-CONTROL DEVICE FOR PHONOGRAIHS Application filed Kay 10, 1929, Serial No. 362,009, and in Germany August 11, 1928.

Driving devices for phonographs are always under tension whilst the other motor known comprising two motors, say a spring is operative, starts automatically whenever and an electric motor, each motor being the speed of the said other motor decreases adapted to be connected in turn with the turn- (for instance on the case of an electric motable shaft through controlled clutches or tor through a decrease in the feed voltage) through automatic couplings of the free so as to keep the speed of the turn-table shaft wheel type. constant. When the spring motor is alone Thus the phonograph may be driven either operative the second motor is stopped. In by winding up by hand the spring of the first the arrangement disclosed hereinbelow no 10 motor, connecting said motor with the turncontrol device is required for stopping the table shaft and then allowing the spring mospring motor when the electric motor is tor to start working, the other motor being switched in and for cutting ofl the electric disconnected or else electrically by connectmotor when the spring motor is started.

ing the electric motor with the shaft and feed- My improved control device comprises thus 15 ing it with electric current, the spring motor a spring motor, a second motor, say an electric being disconnected. The phonograph may motor and a differential mechanism conthus be driven under all circumstances. trolled simultaneously by each of the two mo- But such arrangements are complicated tors whilst the second motor is operative and and costly. I have already proposed the supcontrolling the turn-table shaft, means being 20 pression of any clutches or couplings by conprovided for preventing the differential necting permanently the spring and the elecmechanism from driving the second motor tric motor with the turntable shaft through when controlled by the spring motor. For a differential gear always in mesh with the instance a non-reversible connection may be motors and with the shaft. A suitable conprovided between the shaft of the second mo- 25 trol device allows the spring motor to be tor and the differential mechanism. started and the current to be switched ofi si- I have described hereinbelow by way of exmultaneously or to close the circuit over the ample and shown diagrammatically on ap electric motor and to stop simultaneously the pended drawing a side view of a form of exespring motor by means of a catch. The two cution of my invention.

30 motors work thus in alternation. This ar- The turntable shaft P controlling in the rangement has the advantage of allowing usual manner a centrifugal regulator R both motors to be permanently in connection through a worm wheel Q is controlled by an with the turntable shaft through a positive electric motor W of suitable power and by a control mechanism. As this control mechaspring motor A.

35 nism is a differential gear, the shaft is con- The differential mechanism which provides trolled when one of the motors is inoperative the connection comprises a central shaft D only through the other motor which works as mounted between the two plates of the device if the former one did not exist. The parts and provided at its lower end with a pinion C of the differential gear directly driven by the meshing with a pinion C engaging in its turn operative motor control the planet pinions the toothed wheel B of the drum of the spring which bear against those parts ofthe gear motor A. Ahollow spindle H loosely mount- 7 which are held stationary through their died over the central shaft D is provided with rect connection with the inoperative motor, a worm wheel G in mesh with the worm Z carthe planet pinions may thereby drive in their ried b the end ofthe shaft of the electric moturn the turntable shaft. tor so as to provide a nonreversible con- My invention has for its object an improved nection between the controlling motor and the device of this type wherein the winding up controlled shaft D. This latter shaft carries of the spring motor is provided automatically a pinion E whereas the spindle H carries a by the other motor, which is for instance an pinion F the diameter of which is different electric motor; the spring motor which is thus from that of pinion E. Planet pinions showing two tooth-works K, L of different diameter are mounted on spindles secured to a casing M rotatably mounted on the spindle H. The toothwork K of one planet pinion meshes with the pinion E driven by the spring motor whereas the tcothwork L of the other planet pinion meshes with the pinion F driven by the electric motor. The casing M is provided with an outer toothwork N meshing with a toothwork 0 provided on the turntable shaft P.

The spring motor may be wound up through a shaft A acting through a worm on a wormwheel provided on the motor shaft.

The working of the device is as follows: hen the electric motor is started the differential mechanism actuates on one hand through the toothed wheel N the shaft and on the other through the pinion C it winds up the spring motor A which is supposed to be unwound at the time. The shaft P and the tooth-work B rotate with speeds which are in a reverse ratio to the resistance offered by them. As the tension of the spring increases, the speed of the electric motor decreases. After a certain time, the spring of the motor A is wound up to its normal operative tension which is about 80% of its maximum tension. The spring remains then at this tension, the shaft P always rotating at normal speed due to the action of the regulator R.

If the speed of the electric motor V were to vary for any reason whatever, for instance due to variations in the feed current, there is an automatic regularization of the speed of the shaft P. If the electric motor commences to rotate less rapidly, it exerts a lesser strain on the spring motor and the spring may there fore unwind and actuate the differential mechanism. The shaft P receives thus the added speeds due to both motors, the complementary speed received from the spring motor compensatin exactly the diminution of speed due to the falling off of the electric motor. On the contrary if the speed of the electric motor were to increase, the complementary power transmitted thereby to the differential mechanism would be absorbed by the spring of the motor A the tension of which would be increased and by the rubbing between the friction pad and the disc of the regulator R without any substantial modification in the speed of the shaft P. The spring of the motor A acts on the transmission between the electric motor and the turntable shaft so as to damp the effect on the latter of the speed modifications of the motor TV. Its action is somewhat similar to that of a dash-pot connected with a water pipe for regulating its flow; the action of the spring is combined with that of the regulator R for giving the record a perfectly uniform speed.

If it is desired to control the phonograph through the spring motor A, it is sufficient to .Wind thelatter up through a crank acting on the shaft A. The electric motor W which is not fed, is not driven by the differential mechanism because the connection between G and Z is not reversible owing to the pitch chosen for the worm Z. The entire power of the motor A serves for driving the turn-table shaft in this case.

As may be readily seen, my improved levice retains all the advantages f the usual two motor control devices and of my own above disclos d prior diiferential control mechanism whilst showing moreover a perfect automaticity of regulation when electrically con trolled.

What I claim is:

1. Double control device for phonographs comprising a spring motor, a second motor, a difierentia-l mechanism controlled simultaneously by both motors when the second motoris operative, a turn-table shaft controlled by said mechanism and means adapted to prevent the reverse actuation of the second motor by the differential mechanism.

2. Double control device for phonographs comprising a spring motor, an electric motor, a differential mechanism controlled simul taneously by both motors when the electric motor is operative, a turn-table shaft con trolled by said mechanism and means adapted to prevent the reverse actuation of the electric motor by the differential mechanism.

Double control device for phonographs comprising a spring motor, an electric motor, a differential mechanism, a turntable shaft controlled by said mechanism, non-reversible means for permanently and operatively connecting the electric motor and the differential mechanism and reversible means for permanently and operatively connecting the spring motorand the differential mechanism.

4;. Double control device for phonographs comprising a spring motor, an electric motor, a turntable shaft, an intermediary shaft, a toothed wheel keyed thereto and controlled by the spring motor, a spindle concentric with the intermediary shaft, a worm gear connecting said spindle with the electric motor, two pinions of different sizes keyed re spectively to the intermediary shaft and to the spindle, a loosely mounted casing concentric with the intermediary shaft and spindle, a tooth Work on said casing adapted to control the turntable shaft and planet pinions fitted in said casing and provided with two toothworks of different diameters meshing respectively with the pinions on the intermediary shaft and on the spindle concentric therewith.

In testimony whereof I have affixed my signature.

WASSILY REBIKOFF. 

